bits/in.h portability: Patch and RFC

[Robert Millan]

Hi!

I found some possible problem with the portability of the bits/in.h provided
by Glibc. The sysdeps/unix/sysv/linux/bits/in.h version has a number of
macros that aren't defined in sysdeps/generic/bits/in.h, and I suspect a
number of them are not really Linux-specific (Particularly, IPV6_PKTINFO
is defined on GNU/Linux and *BSD systems, and used unconditionaly by bind9)

Before I could dump cleanly the differences between both files, I had to do
some fixes in linux/bits/in.h because due to cosmetical changes they were
out of sync. I'm attaching a little patch (w/ChangeLog) that fixes this.

Once that is fixed, I could obtain a list of the actual differences between
both files. It follows in unified diff format.

If you could commit the attached patch, and have a look at the below macros
to give an indication on which of them are Linux-specific and which should
be added to generic/bits/in.h, that'd be much appreciated.

--- generic/bits/in.h   2003-06-28 10:25:50.000000000 +0200
+++ unix/sysv/linux/bits/in.h   2004-04-10 17:55:08.000000000 +0200
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997, 2000 Free Software Foundation, Inc.
+/* Copyright (C) 1991-1999, 2000 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -16,34 +16,50 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
-/* Generic version.  */
+/* Linux version.  */
 
 #ifndef _NETINET_IN_H
 # error "Never use <bits/in.h> directly; include <netinet/in.h> instead."
 #endif
 
-/* Link numbers.  */
-#define        IMPLINK_IP              155
-#define        IMPLINK_LOWEXPER        156
-#define        IMPLINK_HIGHEXPER       158
-
-
 /* Options for use with `getsockopt' and `setsockopt' at the IP level.
    The first word in the comment at the right is the data type used;
    "bool" means a boolean value stored in an `int'.  */
-#define        IP_OPTIONS      1       /* ip_opts; IP per-packet options.  */
-#define        IP_HDRINCL      2       /* int; Header is included with data.  
*/
-#define        IP_TOS          3       /* int; IP type of service and 
precedence.  */
-#define        IP_TTL          4       /* int; IP time to live.  */
-#define        IP_RECVOPTS     5       /* bool; Receive all IP options 
w/datagram.  */
-#define        IP_RECVRETOPTS  6       /* bool; Receive IP options for 
response.  */
-#define        IP_RECVDSTADDR  7       /* bool; Receive IP dst addr 
w/datagram.  */
-#define        IP_RETOPTS      8       /* ip_opts; Set/get IP per-packet 
options.  */
-#define IP_MULTICAST_IF 9      /* in_addr; set/get IP multicast i/f */
-#define IP_MULTICAST_TTL 10    /* u_char; set/get IP multicast ttl */
-#define IP_MULTICAST_LOOP 11   /* i_char; set/get IP multicast loopback */
-#define IP_ADD_MEMBERSHIP 12   /* ip_mreq; add an IP group membership */
-#define IP_DROP_MEMBERSHIP 13  /* ip_mreq; drop an IP group membership */
+#define        IP_OPTIONS      4       /* ip_opts; IP per-packet options.  */
+#define        IP_HDRINCL      3       /* int; Header is included with data.  
*/
+#define        IP_TOS          1       /* int; IP type of service and 
precedence.  */
+#define        IP_TTL          2       /* int; IP time to live.  */
+#define        IP_RECVOPTS     6       /* bool; Receive all IP options 
w/datagram.  */
+/* For BSD compatibility.  */
+#define        IP_RECVRETOPTS  IP_RETOPTS       /* bool; Receive IP options 
for response.  */
+#define        IP_RETOPTS      7       /* ip_opts; Set/get IP per-packet 
options.  */
+#define IP_MULTICAST_IF 32      /* in_addr; set/get IP multicast i/f */
+#define IP_MULTICAST_TTL 33    /* u_char; set/get IP multicast ttl */
+#define IP_MULTICAST_LOOP 34   /* i_char; set/get IP multicast loopback */
+#define IP_ADD_MEMBERSHIP 35   /* ip_mreq; add an IP group membership */
+#define IP_DROP_MEMBERSHIP 36  /* ip_mreq; drop an IP group membership */
+
+#define IP_ROUTER_ALERT    5   /* bool */
+#define IP_PKTINFO         8   /* bool */
+#define IP_PKTOPTIONS      9
+#define IP_PMTUDISC        10  /* obsolete name? */
+#define IP_MTU_DISCOVER    10  /* int; see below */
+#define IP_RECVERR         11  /* bool */
+#define IP_RECVTTL         12  /* bool */
+#define IP_RECVTOS         13  /* bool */
+
+
+/* IP_MTU_DISCOVER arguments.  */
+#define IP_PMTUDISC_DONT   0   /* Never send DF frames.  */
+#define IP_PMTUDISC_WANT   1   /* Use per route hints.  */
+#define IP_PMTUDISC_DO     2   /* Always DF.  */
+
+/* To select the IP level.  */
+#define SOL_IP 0
+
+#define IP_DEFAULT_MULTICAST_TTL        1
+#define IP_DEFAULT_MULTICAST_LOOP       1
+#define IP_MAX_MEMBERSHIPS              20
 
 /* Structure used to describe IP options for IP_OPTIONS and IP_RETOPTS.
    The `ip_dst' field is used for the first-hop gateway when using a
@@ -61,9 +77,27 @@
     struct in_addr imr_interface;      /* local IP address of interface */
   };
 
-/* IPV6 socket options.  */
+/* As above but including interface specification by index.  */
+struct ip_mreqn
+  {
+    struct in_addr imr_multiaddr;      /* IP multicast address of group */
+    struct in_addr imr_address;                /* local IP address of 
interface */
+    int        imr_ifindex;                    /* Interface index */
+  };
+
+/* Structure used for IP_PKTINFO.  */
+struct in_pktinfo
+  {
+    int ipi_ifindex;                   /* Interface index  */
+    struct in_addr ipi_spec_dst;       /* Routing destination address  */
+    struct in_addr ipi_addr;           /* Header destination address  */
+  };
+
+/* Options for use with `getsockopt' and `setsockopt' at the IPv6 level.
+   The first word in the comment at the right is the data type used;
+   "bool" means a boolean value stored in an `int'.  */
 #define IPV6_ADDRFORM          1
-#define IPV6_RXINFO            2
+#define IPV6_PKTINFO           2
 #define IPV6_HOPOPTS           3
 #define IPV6_DSTOPTS           4
 #define IPV6_RTHDR             5
@@ -71,16 +105,25 @@
 #define IPV6_CHECKSUM          7
 #define IPV6_HOPLIMIT          8
 
-#define IPV6_TXINFO            IPV6_RXINFO
-#define SCM_SRCINFO            IPV6_TXINFO
 #define SCM_SRCRT              IPV6_RXSRCRT
 
+#define IPV6_NEXTHOP           9
+#define IPV6_AUTHHDR           10
 #define IPV6_UNICAST_HOPS      16
 #define IPV6_MULTICAST_IF      17
 #define IPV6_MULTICAST_HOPS    18
 #define IPV6_MULTICAST_LOOP    19
 #define IPV6_JOIN_GROUP                20
 #define IPV6_LEAVE_GROUP       21
+#define IPV6_ROUTER_ALERT      22
+#define IPV6_MTU_DISCOVER      23
+#define IPV6_MTU               24
+#define IPV6_RECVERR           25
+#define IPV6_V6ONLY            26
+#define IPV6_JOIN_ANYCAST      27
+#define IPV6_LEAVE_ANYCAST     28
+#define IPV6_IPSEC_POLICY      34
+#define IPV6_XFRM_POLICY       35
 
 /* Obsolete synonyms for the above.  */
 #define IPV6_ADD_MEMBERSHIP    IPV6_JOIN_GROUP
@@ -88,6 +131,15 @@
 #define IPV6_RXHOPOPTS         IPV6_HOPOPTS
 #define IPV6_RXDSTOPTS         IPV6_DSTOPTS
 
+/* IPV6_MTU_DISCOVER values.  */
+#define IPV6_PMTUDISC_DONT     0       /* Never send DF frames.  */
+#define IPV6_PMTUDISC_WANT     1       /* Use per route hints.  */
+#define IPV6_PMTUDISC_DO       2       /* Always DF.  */
+
+/* Socket level values for IPv6.  */
+#define SOL_IPV6        41
+#define SOL_ICMPV6      58
+
 /* Routing header options for IPv6.  */
 #define IPV6_RTHDR_LOOSE       0       /* Hop doesn't need to be neighbour. */
 #define IPV6_RTHDR_STRICT      1       /* Hop must be a neighbour.  */

-- 
Robert Millan

"[..] but the delight and pride of Aule is in the deed of making, and in the
thing made, and neither in possession nor in his own mastery; wherefore he
gives and hoards not, and is free from care, passing ever on to some new work."

 -- J.R.R.T., Ainulindale (Silmarillion)

bits_in.diff
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